Respuesta :
Answer:
The cost of plans is same for 120 minutes.
Step-by-step explanation:
Given:
One cellular phone charge = $26.50 a month and $0.15 per minute.
Another cellular charges = $14.50 a month and $0.25 per minute.
Let the number of minutes at which both plans are same be = [tex]x[/tex] minutes
For [tex]x[/tex] minutes the plan charges are as following:
1)[tex]$(26.50 + 0.15x)[/tex]
2)[tex]$(14.50 + 0.25x)[/tex]
So, we equate the above expressions as the plans are same.
[tex]26.50 + 0.15x=14.50 + 0.25x[/tex]
Multiplying both sides by 100.
[tex]100\times(26.50 + 0.15x)=(14.50 + 0.25x)\times 100[/tex]
[tex]2650 + 15x=1450 + 25x[/tex]
Subtracting both sides by 1450.
[tex]2650 + 15x-1450=1450 + 25x-1450[/tex]
[tex]1200 + 15x=25x[/tex]
Subtracting both sides by [tex]15x[/tex]
[tex]1200 + 15x-15x=25x-15x[/tex]
[tex]1200=10x[/tex]
Dividing both sides by 10.
[tex]\frac{1200}{10}=\frac{10x}{10}[/tex]
[tex]120=x[/tex]
∴ [tex]x=120\ minutes[/tex]
The cost of plans is same for 120 minutes.
